Wells Fargo customers took to Twitter Friday to complain about an apparent mix-up that sent emails addressed to other people into their inboxes.

"My name IS NOT Susan Miller. You're lucky none of her personal information was in this email," wrote Ashley Jean.

"Hey @WellsFargo should I be concerned about receiving an email with someone else's name on it? Is it an error with mail merging or a security issue?" asked Sarah Knox.

The email warned customers about a technical problem that temporarily caused eBills accounts to reflect a balance of zero. The bank may have fixed the glitch, but created a new problem altogether when it sent out the incorrectly addressed emails.

Several customers expressed concerns online about the security of their data. Wells Fargo has been trying to win people's trust back with a national television ad campaign, but the Chronicle found reaction to the apology in a survey was only lukewarm.

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This time for its 401k practices.

Media: Fortune

The Consumer Financial Protection Bureau and the Office of the Comptroller of the Currency fined Wells Fargo $1 billion for various wrongdoings, including creating fake accounts under customers' names and pressuring customers into purchasing unnecessary auto insurance.